It is often desirable for planar optical devices to exchange light signals with one another. A variety of systems stack the optical devices on top of one another. In these systems, the optical devices include ports that allow light signals to exit or enter the device through either the top of the device or the bottom of the device. In order for these ports to operate successfully, a variety of features are often added to the device. For instance, lenses and other optical component are often added to the device and/or placed between different devices in order correct for the direction, size, and/or shape of the light signal as it travels between the devices. Additionally, these ports often require the formation of reflecting surfaces at particular angles relative to other components in the device. For instance, these ports often require the formation of a reflecting surface angled at precisely 45° relative to the bottom of the device. These features add cost and complexity to the systems and are often a source of optical loss within the system. As a result, there is a need for optical devices that can be stacked with reduced levels of complexity.